Forest Green
ACCESS: Above Top Secret
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It all depends how wide the warhead bus is. Payload is irrelevant if the bus only has enough area for X warheads.
FWIW, back in 1975, RAND reckoned that a missile using then-current technology - that is, the Peacekeeper technological base - would have double the throw-weight for the same (6,000 nautical mile) range.It may be able to support somewhat heavier RVs, but it's still going to max out at 3 (assuming a MM3 OML as concepts have used).
So I think Sentinel is going to be longer ranged due to lighter stages.
No, it isn't/. Not with chemical rockets. Just a stage with no payload, possible. With payload and wings, no way.Come on now, a SSTO Spaceplane is hardly warp drive level. It's basically doable, it's just that nobody has poured the cash into it yet.
It is not even RTLS, it is launching in the first place over inhabited land. Chinese or Middle East don't count. Western world values are at play here.If you RTLS over land,
or longer rangeIt may be able to support somewhat heavier RVs, but it's still going to max out at 3 (assuming a MM3 OML as concepts have used).
So I think Sentinel is going to be longer ranged due to lighter stages.
That is exactly why NASA came up with TRLs.Come on now, a SSTO Spaceplane is hardly warp drive level. It's basically doable, it's just that nobody has poured the cash into it yet. A warp drive requires negative mass, which hasn't even been discovered yet, to even hold together even the faintest dream of it ever being a reality.
Someone disagrees apparently.No, it isn't/. Not with chemical rockets. Just a stage with no payload, possible. With payload and wings, no way.
This is not an SSTO. A sled on a track is a stage.Someone disagrees apparently.
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Radian Aerospace – World’s First Single-Stage-to-Orbit Spaceplane
Radian Aerospace is building a next-generation spaceplane planned to be the world's first single-stage-to-orbit, truly reusable space vehicle operating in Low Earth Orbit.www.radianaerospace.com
It would need a 2 mile long runway as any large aircraft, even a 747 needs that, so not really a constraint. There's also the Skylon, plus advancements in RDE scramjets and rockets, which are vastly more efficient than traditional rockets.This is not an SSTO. A sled on a track is a stage.
Ha! "A revolutionary 2-mile-long rail sled system eliminates the constraints of vertical systems" and adds more of its own like requiring a launch flat launch area and limited launch azimuths.
5000lb payload? Not very competitive.
It would need a larger area than an airportIt would need a 2 mile long runway as any large aircraft, even a 747 needs that, so not really a constraint. There's also the Skylon, plus advancements in RDE scramjets and rockets, which are vastly more efficient than traditional rockets.
That comment makes no sense. Some airports have 3 mile long runways, often more than one too, plus taxiways.It would need a larger area than an airport
25% seems a decent amount.It would need a larger area than an airport
Skylon? Might as well had said fusion power, it just around the corner too.
A little more ISP from RDE is not going to change things. Max ISP is still limited.
Not for H2 and O2. RS-25 and RL10 are already near the maximum possible. And that is for all chemical rocket that don't use Florine or Beryllium (or other toxic substances)That comment makes no sense. Some airports have 3 mile long runways, often more than one too, plus taxiways.
25% seems a decent amount.
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Rotating detonation engine - Wikipedia
en.wikipedia.org
You sure about that?Not for H2 and O2. RS-25 and RL10 are already near the maximum possible. And that is for all chemical rocket that don't use Florine or Beryllium (or other toxic substances)
yes, because can't fix the losses like:
According to NASA the RDREs have 15% better Isp but the RDREs themselves are more compact, which reduces mass.yes, because can't fix the losses like:
Where does the remaining energy go? Some is stored in the motion of the exhaust: in intramolecular vibrations and rotations, and kinetic energy in directions perpendicular to the rocket’s travel. Some is also used to heat (and boil) the two cryogenic liquids from their stored temperature to their combustion one (a quick estimate factoring in only latent heat of vaporisation of oxygen brings the upper bound down to 520s)."
also, to heat some LOX and LH2 into GOX and hot H2 to pressurize the External tank.
The point is that ISP can't improved enough to make a reusable SSTO with wings viable.
It is commonly cited that the peak benefit to detonative combustion devices is the promised ~15% boostin specific impulse (Isp) compared to the maximum theoretical Isp in an equivalent constant pressure (CP)combustor. However, other major performance characteristics are advantages with these engines ratherthan quantities such as Isp and thrust. For one, these engines are often much more compact allowing forreduced hardware mass a geometry. The completion of combustion has been shown to occur much fasterthan CP combustors and thus drastically reduces L* requirements as well as the potential to maximizecharacteristic velocity (C*) efficiency. Other works have suggested that these combustion devices couldproduce lower overall heat fluxes and lower total heat load to active cooling geometries. In addition, lessonslearned from the literature indicates that the heat flux curve in a detonative combustor may decrease as theflow gets closer to the chamber exit. This would allow for the design of ultra-low pressure drop integratedcoolant channels, which is another major performance advantage for this engine type. Each of theseperformance criteria make a strong case for investment into detonative combustion device technologies.
still not going to help enough.According to NASA the RDREs have 15% better Isp but the RDREs themselves are more compact, which reduces mass.
yes, we can. The margins are so slim even for an expendable one. And no, it is not saving "massive" weight and hence not "lot of gains". A Raptor engine only weighs 3,500 lbs. It wouldn't be much smaller. More compact RDE is inches and not feet. The nozzle dominates the length of the engine, the combustion chamber is a fraction of it.There's no way we could know that. Smaller engines mean smaller body around engines, both of which save massive weight, which means smaller wings, which saves more weight + reduced cooling weight + higher rocket Isp + massively higher air-breathing Isp. Lot of gains there.
Don't think we can even nearly rule out viability, but whether it will be commercially viable is another question.
It was two stage, so what is your point?That's sort of why I like stage-a-half systems.
Titan II was the closest thing to an SSTO yet made.
There are no TAVs and only the Shuttle and SLS use SRBs.Now TAVs used a single SRB right?
Big, ugly solid to take abuse--small TAV/bus on top.
TAVs were not built due to lack of interest and funding. The design studies were done by Boeing in the 80's.It was two stage, so what is your point?
There are no TAVs and only the Shuttle and SLS use SRBs.
what abuse? The payloads see most of the loads.
Lack of need.TAVs were not built due to lack of interest and funding.